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The purpose of this paper is to explore the effect of ZnO on the structure and properties of micro-arc oxidation (MAO) coating on rare earth magnesium alloy under large concentration gradient.

The macroscopic and microscopic morphology, thickness, surface roughness, chemical composition and structure of the coating were characterized by different characterization methods. The corrosion resistance of the film was studied by electrochemical and scanning Kelvin probe force microscopy. The results show that the addition of ZnO can significantly improve the compactness and corrosion resistance of the MAO coating, but the high concentration of ZnO will cause microcracks, which will reduce the corrosion resistance to a certain extent.

When the concentration of zinc oxide is 8 g/L, the compactness and corrosion resistance of the coating are the best, and the thickness of the coating is positively correlated with the concentration of ZnO.

Too high concentration of ZnO reduces the performance of MAO coating.

The MAO coating prepared by adding ZnO has good corrosion resistance. Combined with organic coatings, it can be applied in corrosive marine environments, such as ship parts and hulls. To a certain extent, it can reduce the economic loss caused by corrosion.

The effect of ZnO on the corrosion resistance of MAO coating in electrolyte solution was studied systematically, and the conclusion was new to the common knowledge.

This study aims to analyze the relationship between corporate social responsibility (CSR) and quality of accounting report, especially on earnings management (EM). In addition, potential moderators of this relationship are examined.

After a comprehensive study of potential mechanisms, the authors obtain plenty of empirical results to open the black box of the link between CSR and EM. Meta-analysis is applied on 51 studies from 35 papers. Further analysis is also carried out to determine the moderating effects, such as the cultural and sample selection differences in these papers.

CSR is negatively associated with EM. In addition, this effect is moderated by cultural difference, CSR measurement, and year of sample selection.

Two patterns of the hypothesis between CSR and EM are confirmed based on agency cost theory, a theoretical shift of corporate ethics based on organizational moral perspective. Several useful suggestions are also provided for future studies on the empirical model and sample selection. Further research is necessary to clarify the agency cost behind the two theoretical patterns.

CSR is not a tool for firms to market but rather a strategy to ensure their consistency with moral principles, indicating that management should pay more attention to the potential damage of the incongruence between CSR and accounting reporting quality. CSR reporting quality remains an important issue for legislature to guarantee continued firm operations.

To the best of the authors’ knowledge, this study is the first to analyze the CSR and EM link using a meta-analysis and to consider its underlying mechanism under the global environment. Previous method design and sample selection are reviewed to provide reference for future studies.

The purpose of this paper is to investigate the influence of praseodymium (Pr) additions (0, 0.05 and 0.5 wt%) on the mechanical properties and microstructure of SnAgCu solder joint during aging process. Moreover, the authors aim to indicate that the decreased soldification undercooling of Sn3.8Ag0.7Cu solder can suppress the formation of Ag3Sn plate to some extent.

The shear strength evolution of SAC, SAC‐0.05Pr and SAC‐0.5Pr solder joint were studied under 150°C aging process with STR‐1000. The effect of Pr additions on the solidification behavior of SnAgCu solder was also studied by differential scanning calorimetry. To study the microstructure evolution, the cross‐sections of all specimens were observed by means of scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). Meanwhile, the etchant, consisting of 20%HNO3+distilled water was used for deep etching to reveal the interfacial morphology.

The shear force reduction rate of SAC solder joint during aging was restrained by 0.05%Pr addition but promoted with 0.5% Pr addition. The growth of IMC layer of SnAgCu joint in the aging process was suppressed significantly by different amounts of Pr additions. However, the beneficial effect of Pr addition due to the suppression of IMC layer growth was weakened by the micro‐cracks formed in PrSn3 compounds in SnAgCu‐0.5Pr joint. Pr additions (0.05, 0.5 wt%) decrease the solidification undercooling of SnAgCu solder, which will suppress the formation of Ag3Sn plate to some extent.

Further studies are necessary for confirmation of the practical application, especially of the manufacturing technology of solder paste containing Pr.

The appropriate amount of Pr in Sn3.8Ag0.7Cu solder is about 0.05 wt%. It is found that SAC‐0.05Pr solder has an improvement in solder joint reliability in long aging processes. The results suggested the novel solder alloys can meet the requirements of high reliability application.

The paper demonstrates that: Pr additions promote the solidification of SAC solder; shear force reduction rate of SAC solder joint was reduced by 0.05%Pr addition; the IMC layer growth rate of SnAgCu solder joint was suppressed by Pr additions; and micro‐cracks were found in PrSn3 phases after aging.

The purpose of this paper is to investigate the explosive performance and explosion damage mechanism of T-beam bridge structure.

On the basis of the existing specification, two T-beam bridge models were designed and fabricated. Test specimens of different explosive dosage and different blast height were carried out. The mechanical process, failure mode, blast damage model, damage identification mechanism and blast evolution law and quantitative evaluation were taken into account.

The results revealed that the web plate fracture failure is the key to the unstable failure of the whole T-beam bridge. The explosion failure phenomenon and blast damage evaluation criterion of RC T-beam bridge was divided into five stages: the original cracks stage of concrete material (D = 0 ∼ 0.1), the fractures initiation stage of concrete material (D = 0.1 ∼ 0.3), the stable expansion stage of cracks in concrete material (D = 0.3 ∼ 0.55), the unstable expansion stage of cracks in concrete material (D = 0.55 ∼ 0.8), the explosion fracture of steel bars and the overall instability and damage of the bridge (D = 0.8 ∼ 1.0), which can also be described as basically intact, slight damage, moderate damage, severe damage and collapsed.

The research result will provide basis for the antiknock evaluation and damage repair technical specifications of the RC T-beam bridge.

The research results of damage evaluation serve as a basis for damage repair and reinforcement of bridge structures after explosion.

The purpose of this paper is to investigate the impacts of the 2008 Chinese stimulus program on earnings management.

Using a sample period from 2004 to 2011 (per-stimulus period: 2004-2007 and post-stimulus period: 2008-2011), the authors compare the change in earnings management between the firms that received the stimulus funds and those that did not receive the stimulus funds.

The authors find that from the pre- to post-stimulus period, the recipient firms experienced a greater increase in downward accrual management and a greater decrease in real management than the non-recipient firms did. This result is primarily driven by the non-state-owned enterprises and firms using non-Big-Four auditors.

The results suggest that the earnings management level is ultimately determined by the underlying economic and political factors influencing managers’ and auditors’ incentives (Cohen, 2008; Ball et al., 2003). Meanwhile, some mechanisms, such as high-quality audit (Eshleman and Guo, 2014) and state ownership (Wang and Yung, 2011) can also play a role in determining the level of earnings management.

The purpose of this paper is to measure the turnover (or stability in employment) of village clinicians in rural China over the past decade. The authors also want to provide quantitative evidence on the individual characteristics of the clinicians who provide health care to villagers in rural China and whether we should expect these individuals to be interested in continuing to supply quality health care in China’s villages in the coming years.

This paper uses data from a survey of rural China’s village clinicians conducted in five provinces, 25 counties, and 101 villages in 2005 and 2012. This paper also uses qualitative data from interviews with 31 village clinicians. Using a mixed methods approach, this study describes the turnover of village clinicians and the main factors that impact the career decisions of clinicians.

Turnover of China’s village doctors, while not trivial (about 25 percent of village doctors exited their field between 2005 and 2012), is still not overly high. Only five out of 101 villages did not have village clinicians in 2012. Of those that lost village doctors between 2005 and 2012, nearly all of them still had a village doctor in 2012 (either taken over by another local clinician or the position was taken by a newcomer). The authors find that three main sets of factors are correlated with the career decisions of village clinicians: village clinicians’ opportunity cost, the profitability of running a village clinic, and commitment to the field of medicine. In general, clinicians who left the village faced a much higher opportunity cost, had been running a clinic that was not profitable, and had fewer ties to the field of medicine. Newcomers over the same period had higher levels of education, went to higher profit clinics between 2005 and 2012, and had a stronger commitment to the field.

This study makes use of a data set with a large and nationally representative sample to provide a new perspective to better understand clinician turnover at village clinics, the career decisions of clinicians, and the implied trends for the quality and access to rural health care services in the future.

In recent years, high‐speed recording CD‐R has already become the mainstream of CD‐R market. Therefore, to promote the efficiency of recording CD‐R is of significant importance. This study uses Taguchi’s parameter design to improve the yield rate for the process of CD‐R substrate. We have found 13 three‐level controllable factors from the fishbone diagram, repeted 10 times the experiment with the L₂₇(3¹³) orhogonal array, and measured seven quality characteristics. We employ four general methods to find the optimal parameter conditions individually. Then, we perform the confirmation experiement and compare the results. Finally, we obtain the optimal parameter conditions. According to the analysis of benefits, the optimal parameter conditions can reduce the quality loss of CD‐R substrte to about 21 per cent. In the future, the results can be extended to other research of DVD‐R substrate.

The purpose of this paper is to establish a situation evaluation model of the robot and ball in SimuroSot5vs5 platforms and enhance the strength of the team in a SimuroSot5vs5.

This paper presents a mathematical model based on situation evaluations which can improve the strength of the team in SimuroSot5vs5. The situation evaluation focus on four aspects includes scores of both sides, possession of teams on ground, ball strategy, and treat. The statistical analysis of the score can verify validity and stability of current strategy in confrontation. To evaluate the situation more effectively without blindness, possession on both teams is, respectively, evaluated. Ball strategy analyzes coordinate transformation to the ball on the ground and illustrates the circumstance of both teams on the offensive position accurately in length and breadth. To know the circumstance on the field more completely and synthetically, a threat situation evaluation model is built. An effective and practical algorithm for comprehensive situation evaluation is successfully finished. The experiments prove validity and performance of the proposed situation evaluation model.

A mathematical model is designed to achieve situation evaluation, and the strategy can change in accordance with different situations on the ground.

The system is specifically applied to SimuroSot5vs5 platform. The extensibility of the system is limited.

When the robot and ball is in high speed movement, a large calculated amount will slow the speed of the system.

The paper shows that situation evaluation in SimuroSot decision support systems will enhance the battle effectiveness of the soccer team.

This study aims to report the preparation, selective laser sintering (SLS) processing and properties of a new nylon elastomer powder. The effects of solvent, dissolution temperature and time and cooling method and speed on the particle size and morphologies of the prepared nylon elastomer powder are investigated.

The prepared nylon elastomer power possesses the particle size of around 50 mm and is spherical in shape, indicating that this study provides the feasible dissolution-precipitation process, a distillation cooling method and a suitable solvent to prepare nylon elastomer powders.

Compared to pure nylon 12, the nylon elastomer has a lower part bed temperature and a wider sintering window for the SLS process. The wider sintering window indicates the better SLS processibility. The lower part bed temperature is beneficial to the recycling of material and the decrease in the requirement of SLS equipment.

The nylon elastomer in this study has a lower part bed temperature and a wider sintering window for the SLS process. The wider sintering window indicates better SLS processibility. The lower part bed temperature is beneficial to the recycling of material and the decrease in the requirement of SLS equipment.